Measuring instrument



c. E; BARCLAY MEASURING INSTRUMENT April 18, 1950 2 Sheets-Sheet 1 Filed Aug. 7 1946 Inventor A tto meys April 18, 1950 Filed Aug. 7, 1946 C. E. BARCLAY MEASURING INSTRUMENT 2 Sheets-Sheet 2 UIIIIIIIIIII/li Im'entm' CZEBaro Z a Attorney:

Patented Apr. 18, 1950 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to a measuring instrument especially adapted for use by carpenters in lay-out work and which can be accurately employed for measuring the hypotenuse of a right angle triangle both as to degree and length.

More particularly, it is an aim of the invention to provide a measuring instrument which is especially useful in laying out length and miter cuts for complicated roofs, rafters, braces and stair runs and which will save considerable time in lay-out work and eliminates the necessity of making scale drawings to ascertain degree and linear measurements.

Still a further aim of the invention is to prvide an instrument which is relatively small in size as compared to a common square and as compared to the actual size of rafters, braces and stair runs but which is provided with means for obtaining fine linear measurements thereon, so that by measurements obtained with the instrument the lay-out work will be extremely accurate when utilized in the actual construction work.

Numerous other objects and advantages of the instrument will hereinafter become more fully apparent from the following description of the drawings, which illustrate a preferred embodiment thereof, and wherein:

Figure 1 is a top plan view of the measuring instrument;

Figure 2 is a cross sectional view thereof, on an enlarged scale, taken substantially along a plane as indicated by the line 22 of Figure 1;

Figure 3 is a similar view taken substantially along a plane as indicated by the line 3-3 of Figure 1;

Figure 4 is a cross sectional view taken substantially along a plane as indicated by the line 4- of Figure 1, and on an enlarged scale;

Figure 5 is an enlarged longitudinal sectional view taken substantially along a plane as indicated by the line 5-5 of Figure 1;

Figure 6 is a plan view of one part of the instrument and looking toward the opposite side thereof to thatas seen in Figure 1, and

Figure '7 is a cross sectional view taken substantially along a plane as indicated by the line 'l-'! of Figure 1.

Referring more specifically to the drawings, the improved lay-out or measuring instrument in its entirety is designated generally 8 and includes a square 9 composed of a blade l9 and tongue II. The square 9 is one-quarter of the size of a common square and the blade H) and tongue II are provided with graduation markings ii on the upper side thereof and which extend inwardly from the outer edges of the parts II it and l I. Certain of the correspondingly spaced graduation markings of the parts I0 and II are numbered consecutively beginning 1, 2 etc. beginning from the apex of the square 8. The space or distance between the adjacent numbered markings I2 is in each case equal to one quarter of an inch. The blade I0 is also provided with graduation markings l3 along a portion of the inner edge thereof and on the upper side of the blade and said markings are likewise numbered consecutively toward the outer end of the blade l0 and beginning 1, 2 etc. As clearly illustrated in Figure 1, the graduation l3 which is transversely aligned with the graduation l2 numbered 6 bears the number 1. It will thus be apparent that the numbering of the graduations l2 and I3 differ by five-quarters of an inch, for a purpose which will hereinafter become apparent.

A plate I4 is disposed against the upper side of the blade l0 and lengthwise thereof and is mounted for sliding movement lengthwise of said blade. The plate [4 is provided with a rearwardly projecting shoulder [5 having an upwardly opening groove 16 in the inner part thereof to slidably engage the outer edge of the blade ill, as best seen in Figure 2. Above the shoulder IS, the plate I4 is provided with a struck-out portion forming an opening I! and said struckout portion extends rearwardly and is disposed above the shoulder l5 to provide a flange 18 which is located inwardly of the inner edge of the blade II], when the outer edge of said blade is in engagement with the groove or channel It. The flange I8 is provided with a threaded opening H? to receive a thumb screw 20, the head of which is partially disposed in the opening [1, and the terminal of the shank end of which is adapted to be moved into and out of engagement with the inner edge of the blade III to clamp or release the plate I4 relatively to said blade.

The plate I 4 is provided with an arcuate inner edge 2] and the upper side or outer side of the plate I4 is provided with radially disposed graduation markings 22 which extend inwardly from the edge 2! and which are indicated by degree markings 23 at ten degree intervals from 0 to degrees. The plate [4 is provided with an arcuate slot 24 which is disposed concentric with the edge 2| and over which a protractor arm 25 is swingably disposed on a pivot 26 of the plate M, the axis of which intersects with the outer edge of the blade 10. As best seen in Figure 7, the arm 25 is provided with an opening 26 to receive the threaded shank of a thumb screw 21 which engages the threaded bore of a nut 28. The nut 28 is provided with an enlarged outer portion 29 which engages the rear side of the plate M, and a restricted inner portion 39 which slidably engages the groove 24, so that by tightening the thumb screw 21 the portion 29 will coact with the screw 21 to clamp the arm 25 against the plate l4 and prevent swinging movement thereof on its pivot 26.

The upper outer side of the protractor arm 25 is provided with scale markings or graduations 3| which project from the inner edge thereof and corresponding graduations of which are numbered consecutively beginning with 6 from adjacent the inner toward the outer end of the arm 25, and which numbered graduations 3| are spaced the same distances apart as the numbered graduations l2 and I3. As clearly illustrated in Figure 1, the inner edge of the protractor arm 25 intersects the axis of the pivot 26.

A micrometer or Vernier, designated generally 32 is slidably mounted on thearm 25 and includes a slide 33 which slidably engages the arm 25 and which is provided with ,aset screw 34 which is adjustable for clamping the slide to the arm 25 at any desired position thereon. The slide 33 includes the inwardly projecting extension 25 which is disposed beneath the arm 25 and to which a disk segment 3.6 is rotatably connected.

The disk segment 36 is disposed between the extension 35 and the arm 25 and the axis of the pivot 3'! thereof is one thirty-second of an inch ofi center with respect to diametrically opposed edge portions of the disk segment 36. The diameter of the disk segment 36 is equal to one inch so that by rotating said disk segment 35 through an arc of 180 degrees the edge of .the disk 35 will be displaced with respect to the arm 25 a distance equal to one-sixteenth of an inch. The upper surface of the disk36 is provided with graduations 38 which extend inwardly from the arcuate edge thereof, which cover an area equal'to 180 degrees thereon and of which there are twenty-four.

The distance between the outer edge 39 of the plate [4 and the axis of the pivot .26 is equal to one and one-quarter, inches so that by using the edge 39 as an index line with the scale or graduations l3, it is possible to accurately read the distance that the pivot 26 is spaced from the inner end of the blade I9. For example, as seen in Figure 1, the edge 39 is located substantially on the graduation 1'7 of the scale I3 so that the pivot 26 is located in the same respect to the graduation 17, not visible, of the scale or graduations l2.

Assuming thatit is desired to obtain angle and length of the hypotenuse of a right angle triangle having a base side equal to seventeen feet, a perpendicular side equal to twelve and onequarter feet, the measuring instrument 2 would be set as illustrated in Figure 1. The instrument 8 is constructed in scale and one inch thereon equals four feet on a rafter, brace etc. Consequently, the space between adjacent graduations marked 1, 2.etc., are equivalent to one foot on a brace or rafter. As previously explained, the axis of the pivot 26 is located on the graduation 1'7 of the scale I2. The inner edge of the protractor arm 25 intersects the outer edge of the scale 12 of the tongue II at 12 The inner edge of the arm 25 is equally disposed between a 30 degree and 940 degree graduation 22 of the protractor 2! so that the angle of the hypotenuse desired is 35 degrees. The length of the hypotenuse as measured on the scale 3| is between 21 and 21% feet. As this measurement is not as accurate as is desired, the micrometer or vernier 32 is adjusted so that the base line of the graduations 38 thereof is on the 21% graduation of the scale 3|. The disk 36 is then revolved in a clockwise direction until its arcuate edge intersects with the inner edge of the arm 25 and the outer edge of the tongue H. As there are twenty-four graduations 38 on th disk 36, the space between any two graduations represents one-eighth of an 'inch on the brace or rafter so that, for example, if the disk 36 was rotated degrees or IE graduations before its arcuate edge intersected with the tongue and the arm edges, the exact distance measured on the arm 25 would be twenty-one feet one inch.

Various modifications and changes are contemplated and may obviously be resorted to, without departing from the spirit and scope of the invention as hereinafter defined by the appended claims.

I claim:

1. In a measuring or lay-out instrument, a protractor adapted to be slidably mounted on the blade of a square, a protractor arm pivotally mounted on the protractor and projecting therefrom and intersecting with the tongue of the square and having an inner edge disposed in a plane to intersectwith the axis of its pivot for measuring the angle of the hypotenuse of a right angle triangle on the protractor, said protractor arm being provided with linear graduations, scaled to correspond to the scale of the graduations of the square, and a Vernier or micrometer adjustably carried by the protractor arm including a slide for slidably engaging theprotractor arm and a disk segment eccentrically journaled on the slide and having graduations to function in conjunction with the protractor arm and with an. edge of the tongue of the square for obtaining fine measurements on the linear scale of the protractor arm.

2. A measuring instrument as in claim 1, said disk segment being eccentrically mounted for rotation relatively to the protractor arm whereby the graduated edge thereof will be displaced relatively to a predetermined point on said protractor arm when the disk is revolved.

CHARLES E. BARCLAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 302,767 Olson et a1 July 29, 1884 452,054 Sperry May 12, 1891 503,050 Lantz .Q Aug. 8, 1893 579,952 Campbell Apr. 6, 1897 634,782 waiter; Oct. 10, 1899 820,311 Oehrle May 8, 1906 839,943 Marsh Jan. 1, 1907 1,024,863 Myers Apr. 30, 1912 1,104,123 Lewis .1; July 21, 1914 1,110,968 Southard Sept 15, 1914 1,424,492 Leschen Aug. 1, 1922 FOREIGN PATENTS Number Country Date 109,044 Germany Apr. 8, 1899 

